Question

what is the output of the following commands:

pr -t -n -d -o 10 group12

sort -t: -k3,3 -n /etc/group

Answer 1

Note : First of all the above commands uses some files which may be different in your system and my system . So, I will tell the purspose of above command and provide screeshot of the output of command that I executed in my linux terminal.

So here goes your answer:

1) pr -t -n -d -o10 group12 :  pr command is use to prepare or convert a text file for printing in the console.

• -t : This option will omit the page header and trailers. This will remove the left over space in header or trailer of the page , so you can see the output properly.
• -n : This option will display a line number for each line of text, i.e first line will have line number 1 , and so on.
• -d : This option will insert double space in output . You can see the spacing between two lines in output screenshot below.
• -010 : This option will create a margin space with a numerical offset. Here 10 is the offset which means 10 units of extra margin from default margin.
• group12 : It is the file name.

Output 1)  This is the what the group12 file contains. See below.

Below is the output of pr -t -n -d -o10 group12 command : See how the output is formatted with margin , line numbers and double space between two lines.

2) sort -t: -k3,3 -n /etc/group :   This command is use to sort a text file . This command can be modified by using many options available, to reverse sort, numeric sort, sort on basis of a particular column etc.

• -t = This option is used to use a field separator like : . Here in command the field separator is : . You can see in the output screenshot.
• -k = This option is used to sort on a certain column and specify the column number on the basis of which you want to sort the file. Here it is 3rd column and end at 3rd column.
• -n = This option is used to sort the numeric values /data . Here column 3 is numeric in nature (see screenshot).
• /etc/group = The etc is the directory under which a file named group is present.

Output 2 : This is what the group file contains , (I am sharing a short snap of the file, because the file is long.) Initially you can see the group file is unsorted ( column 3 is unsorted marked red).

Now see below the screenshot,  the group file is sorted based on column 3 .

Hope you understand the explaination and output of the commands. You can try these commands in your linux/unix terminal.

Thanks for asking, Feel free to post doubts below in comment.

Happy Chegging !!